The present invention relates to novel pyranobenzoxadiazole derivatives, pharmaceutical compositions containing said derivatives, use thereof for the therapy of hypertension, asthma, cerebrovascular disorder, angina pectoris or incontinence which causes in mammarian animals inclusive of human being or for hair-growth stimulation and a process for producing the above.
Japanese Patent Laid-open Publication No. Sho 58-67683 (67683/1983) discloses that a compound (Development code No. BRL-34916) of the formula (A): ##STR3## has an activity for lowering blood pressure with respect to spontaneously hypertensive rats.
Br. J. Pharmac. (1986), 88, p.p. 103-111 discloses the possibility that the compound BRL-34915 activates K.sup.+ channel and moves resting potential of membrance to the hyper polarization.
Br. J. Pharmac. (1986), 89, p.p. 395-405 shows that the compound BRL-34915 loosens trachealis of guinea pig and suggests that it has utility as a medicine for the therapy of asthma.
Angiology (1987), 27, pp. 425-431 suggests that a composition for activating K.sup.+ channel is effective for the treatment of arrhythmia and angina pectoris.
Br. J. Pharmac. (1987), 91, pp. 803-813 shows that the compound BRL-34915 loosens uterus of rats. For this fact, it may be effective for preventing premature delivery.
DLO News ROUND-UP No. 312 (1987) shows that the compound BRL-34915 is effective for the medical treatment of incontinence and pain.
WO8800-822-A (Patent Kohyo Koho No. Hei 2-500272) discloses that the compound BRL-34915 is useful for the hair-growth.
However, EP-A-28449 and EP-A-28064 show that the benzopyran derivatives to which the BRL-34915 belongs may undesirably affect the action of the heart.
As the result of the intensive research of novel compounds, therefore, the present inventors have found out that the novel pyranobenzoxadiazole derivatives have strong activity for lowering blood pressure. Then, the present inventors have accomplished the present invention.